Display device



E. H. BODEN DISPLAY DEVICE Nov. 1, 1966 Filed Oct. 7, 1963 INVENTOR n e d o B H w n ATTORNEY United States Patent 3,283,204 DISPLAY DEVICE Evan ll-l. Baden, Emporium, Pa, assignor to Sylvania Electric Products, Inc., a corporation of Delaware Filed 0st. 7, 1963, Ser. N 314,325 5 Claims. (Cl. 31558) This invention relates to a display device and more particularly to a display device of the gaseous cold cathode type.

Although there are numerous cold cathode display devices, known prior art means for displaying illuminated bar graph or histogram information consists, for the most part, of mechanical arrangements or electron discharge devices of a type such as the well-known 6-F6G electron tube. Of the known mechanical devices available, it has been found that each has at least one feature or characteristic which is not as adaptable to a graph-type display device as is an electronic device. Also, an electron discharge device has inherent problems such as heat dissipation capability, power consumption requirements, control of emission, gas, and vacuum levels, and numerous others which have been and continue to be serious deterents to the economical fabrication of a product having the reliability, consistency, and characteristics currently demanded of a bar-graph type of display device.

Therefore, it is an object of the present invention to provide an improved bar-graph type of display device.

A further object of the invention is to enhance the reliability of a bar-graph type display device.

A still further object of the invention is to improve the power and heat dissipation requirements of a bargraph type of display device.

Briefly, these objects are fulfilled in one aspect of the invention by including within a gas-filled and hermetically sealed envelope having a light transparent portion and electrical conductors sealed therein, a cathode having a plurality of metallic fingers longitudinally spaced along and attached at one end to a resistance element. A transparent anode is disposed intermediate the fingers and the viewing portion of the envelope and voltages sufiicient to cause a glow discharge are applied between the anode and cathode by means of electrical connection thereof to the conductors extending through the envelope.

For a better understanding of the present invention, together with other and further objects, advantages, and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the accompanying drawing in which the sole figure is an isometric view of one embodiment of a bar-graph type display device.

Referring to the drawing, an elongated envelope 3 of a light transparent material such as glass or at least an envelope 3 having a light transparent portion also has a hermetically sealed aperture 5, common in the art, through which a gas such as argon and preferably neon is inserted at a pressure suitable for supporting a cold cathode glow. The envelope 3 also has aplurality of electrical conductors 7 sealed therein and extending therethrough.

Within the envelope 3 is a cathode assembly 9 aifixed to and supported by clamps 11 attached to selected condoctors 13 and 15. The cathode assembly 9 includes a substrate 17 of an insulating material which is either transparent or opaque.

Preferably, a transparent material is selected in order to provide an area of increased viewing. A plurality of spaced metallic fingers 19 of a material such as powdered metal, metal ribbons, and numerous similar materials are bonded to the substrate 17 by any one of numerous techniques such as spraying, brushing, painting, screening, or brazing.

These fingers 19 are longitudinally arrayed along the substrate 17 and a resistance element 21 of a material such as carbon is also bonded to the substrate 17 and to one end of each of the longitudinally arrayed fingers 19. Opposite ends of the risistor element 21 are connected to the conductors 13 and 15 by metal straps 23 and 25. An insulator coating 27 of an opaque material is adhered to the resistor element 21 to prevent a glow discharge therefrom.

An anode 29 of an electrically conductive transparent material such a a metallic mesh or glass having a conducting surface is attached to and supported by a conductor 31. This anode 29 is disposed intermediate and spaced from the fingers 19 and a transparent portion of the envelope 3 with the conducting surface thereof facing the fingers 19.

Obviously, alternate embodiments are readily fabricated with a minimum of 'difiiculty. For instance, the cathode assembly 9 and anode 29 may be disposed in horizontal planes; the resistance element 21 may be adhered to the opposite surface of an opaque substrate 17; the envelope 3 may be rectangular in shape with conductors 7 similar to those used in printed circuitry; and numerous other modifications may be made.

As to the operation, a positive potential i applied to the anode 29 which, for example, may be about v. DC. Also, the resistance element 21 which has an ohmic value of about 1,000 has applied thereto a DC. voltage of about 10 v. At these conditions, only the bottom finger will exhibit a visible glow with the other fingers biased beyond ionization. As the voltage applied to the element 21 is reduced, the number of glowing segments will vary in inverse relationship to the voltage applied to the element 21.

Thus, there ha been provided a bar-graph or histogram type of display device having many advantages over those known and available for purchase. For instance, mechan ical devices are either diflicult to maintain, slow to react, expensive, or a combination of all three and offer no competitive comparison to the presented device. Moreover, the known and inherent problems of electron discharge devices such as vacuum tubes are eliminated or at least greatly reduced. Also, the viewing area and readability is enhanced by the transparency of the active elements and the accuracy, repeatability, and extended period of use obtainable from such a device is unusual and unexpected.

While there has been shown and described what is at present considered the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention as defined by the appended claims.

What is claimed is:

1. A display device comprising:

a hermetically sealed envelope having a transparent portion and a plurality of electrical conductors sealed therein and extending therethroug-h, said envelope containing a gas suitable for sustaining a cathode glow,

a resistance element attached at the ends to selected conductors within said envelope,

a plurality of conductive fingers having one end thereof bonded at spaced intervals to said element, and

a transparent conductive anode attached to a conductor within said envelope and disposed intermediate said fingers and said envelope transparent portion.

2. A display device comprising:

a hermetically sealed envelope having a transparent portion and a plurality of electrical conductors sealed therein and extending therethrough, said envelope containing a gas suitable for sustaining a cathode glow,

a resistance element attached at the ends to selected conductors within said envelope, said element having an insulator layer thereon,

a plurality of conductive fingers having one end thereof bonded at spaced intervals to said element, and

a transparent conductive anode attached to a conductor within said envelope and disposed intermediate said fingers and said envelope transparent portion.

3. A display device comprising:

a hermetically sealed envelope having a transparent portion and :a plurality of electrical conductors sealed therein and extending therethrough, said envelope containing a gas suitable for sustaining a cathode glow,

a cathode assembly within said envelope, said assembly including a plurality of conductive fingers bonded at spaced intervals to a resistance element having an insulating layer thereon and the ends thereof connected to selected conductors, said fingers and element bonded to a transparent substrate affixed to selected conductors, and

a transparent conductive anode attached to a conductor within said envelope facing said fingers and intermediate thereto and said envelope transparent portion.

4. A display device comprising:

a hermetically sealed envelope having a transparent portion and a plurality of electrical conductors sealed therein and extending therethrough, said envelope containing a gas suitable for sustaining a cathode glow,

a cathode assembly within said envelope, said assembly including a plurality of spaced conductive fingers bonded to an opaque insulator and a resistance element bonded to the opposite surface thereof, each of said fingers having one end thereof connected at spaced intervals to said element and said element having opposite ends thereof attached to selected conductors, and

a transparent conductive anode attached to a conductor Within said envelope facing said fingers and intermediate thereto and said envelope transparent portion.

5. A display device comprising:

a hermetically sealed glass envelope having a plurality of conductors sealed in one end thereof and extending therethrough, said envelope containing neon gas suitable for sustaining a cathode glow,

a carbon resistance element attached at the ends to selected conductors within said envelope,

a plurality of metallic fingers having one end thereof bonded at spaced intervals to said element, and

a metallic mesh anode attached to a conductor within said envelope and disposed intermediate said fingers and said envelope.

No references cited.

DAVID]. GALVIN, Primary Examiner. 

1. A DISPLAY COMPRISING: A HERMETICALLY SEALED ENVELOPE HAVING A TRANSPARENT PORTION AND A PLURALITY OF ELECTRICAL CONDUCTORS SEALED THEREIN AND EXTENDING THERETHROUGH, SAID ENVELOPE CONTAINING A GAS SUITABLE FOR SUSTAINING A CATHODE GLOW, A RESISTANCE ELEMENT ATTACHED AT THE ENDS TO SELECTED CONDUCTORS WITHIN SAID ENVELOPE, A PLURALITY OF CONDUCTIVE FINGERS HAVING ONE END THEREOF BONDED AT SPACED INTERVALS TO SAID ELEMENT, AND A TRANSPARENT CONDUCTIVE ANODE ATTACHED TO A CONDUCTOR WITHIN SAID ENVELOPE AND DISPOSED INTERMEDIATE SAID FINGERS AND SAID ENVELOPE TRANSPARENT PORTION. 